Grader



F. DOMRES Feb. 7, 1967 GRADER Filed Sept. 26, 1963 5 Sheets-Sheet 1' Feb. 7, 1967 F. DOMRES 3,302,317

GRADER Filed Sept. 26, 1963 3 Sheets-sheet 3 INVENTOR. FiA/A Z/A/ 94/1565 United States Patent 3,302,317 GRADER Franklin Domres, Rte. 1, Onekama Township, Manistee County, Mich. 49675 Filed Sept. 26, 1963, Ser. No. 311,760 8 Claims. (Cl. 37-179) This invention relates to a surface grader, and more particularly to a versatile grader attachment unit to be mounted to the rear of a conventional road construction tractor.

The extensive vehicular equipment necessary for construction of roads represents a very great capital investment. This equipment regularly includes, among other units, bulldozers, large tractors for scooping and hauling dirt to the tracks, and large road scraper vehicles for grading the formed road bed. To provide a road bed with the proper grading effects requires versatile equipment and operative skill. Consequently, separate vehicles are normally employed for this purpose.

Additionally, operators of a conventional grader unit or vehicle have difliculty first spreading dirt or gravel from large piles, and then accurately grading the dirt after it is spread out using the same grader unit. This is because these vehicles are ordinarily constructed and intended for only one of these functions.

Another operational limitation of conventional grader units is the difi'iculty of reasonably accurate grading when the front wheels of the vehicle traverse a stepped surface, e.g. a curb, a plank or beam, etc. As thegrader wheels pass over this abrupt level variation, the adjacent blade either rises excessively out of contact with the surface or gouges deeply.

It is an object of this invention to provide a unique scraper attachment unit having the capacity to accurately achieve controlled high quality grading, and to be attachable as a unit to the rear of a conventional powered tractor such as the type conventionally used for scooping dirt. This enables the tractor to have a double function, eliminating the need for a separate vehicle.

It is another object of this invention to provide a rear mounted grader on a tractor having completely versatile grading effects in all respects.

It is another object of this invention to provide a grader attachment unit having exactly controlled depth regulation, side to side tilt regulation, forward-rearward slant regulation, and moreover capable of being hoisted to a non-grading condition. All of these variations are achieved simultaneously and independently.

Still another object of this invention is to provide a unique new grader unit that is capable of both leveling piles of dirt, gravel, etc., and then of achieving an accurate, smooth surface grading, both with the same unit. Moreover, no parts need be disassembled, removed, manually shifted or altered. The operator achieves both of these functions readily, quickly and easily without moving from his seat.

A further object of thisinvention is to provide a surface grader capable of grading a surface reasonably accurately, even though the front wheels of the tractor traverse an abrupt surface rise or fall. The unit, therefore, can be employed, for example, to first level piles of dirt, then smooth the dirt to a level surface while operating back and forth over a curb or the like.

It is another object of this invention to provide a relatively inexpensive grader unit, costing a small fraction of the cost of special grader vehicles now employed, and capable of being manufactured using conventional met-hods and available materials and parts.

It is another object of this invention to provide a grader unit not only having extremely accurate blade depth control and versatility of operation, but also the capacity to 3,302,317. Patented Feb. 7, 1967 be hoisted to an inactive position enabling the tractor to be employed for scoop loading or some other function without removing the grader attachment.

Another object of this invention is to provide a remov able, attachable grader unit requiring no tools to operate, and requiring no tools even to attach or remove it from the tractor.

These and several other objects of this invention will become apparent upon studying the following specification in conjunction with the drawings in which:

FIG. 1 is a perspective view of a conventional fourwheel drive tractor with the grader unit mounted to the rear thereof and having a convention-a1 scoop loader mounted to the front thereof;

FIG. 2 is a perspective enlarged view of the rear of the apparatus in FIG. 1, illustrating the grader unit;

FIG. 3 is an enlarged, fragmentary, perspective view of the valving control system of the unit in FIG. 2;

FIG. 4 is a side elevational view of the grader unit;

FIG. 5 is a plan view of the grader unit;

FIG. 6 is a fragmentary enlarged perspective view of the mounting junction between the grader unit and the tractor; and

FIG. 7 is a fragmentary, exploded, perspective view of the removable connection between the grader and the tractor.

Referring now specifically to the drawings, the combination 10 illustrated in FIG. 1 includes a tract-or subassembly 12 and a grader subassembly 14, and for illustrative purposes, a front scoop loader subassembly 15.

The tractor subassembly 12 includes a suitable frame 16, an internal combustion engine 1 8, four powered wheels 20 drivingly connected to engine 18 by a drive shaft 22, gear box 24, and a differential (not shown) in accordance with conventional principles. As usual, the wheels are steered with a wheel 17 adjacent the operator's seat 19.

The scoop loader mechanism, including scoop 26, may be attached by its linkage and hydraulic cylinders 21 to the front end of the tractor in conventional manner. It is used in the usual way, without hindrance from the grader subassembly 14.

The grader subassembly 14 is attached as a unit to the rear of the tractor. It includes a mounting support (FIG. 6) which may comprise a generally rectangular shaped rigid steel structure having a top cross piece 28, a pair of spaced, vertical, depending side legs 27 and 29, and a bottom cross piece 25. This mounting support is removably attachable and detachable to a hitch 33. The hitch 33 (FIG. 7) is afiixed by bolts 30 to a rigid vertical plate 31 on the back of the tractor (FIG. 3). The hitch itself normally remains on the tractor. The support can be attached to and removed from the hitch without tools using a special pinned connection. This connection has four main points of attachment. A pair of aligned horizontal pins or bars 35 and 35' is affixed at the opposite sides of the base of hitch 33, and more specifically to the base of plates 49 and 51. These interlock with a downwardly opening pair of slots 37 in the bottom of legs 27 and 29 of support 28 (FIGS. 2, 6 and 7). The top of support 28 is secured by the interconnection of transverse, L-shaped locking pins 39 and 41 (FIGS. 6 and 7) which fit slidably through openings 43 in opposite sides of support 28 and through openings 45 and 47 respectively in the pair of spaced, rearwardly projecting flanges 49 and 51 of hitch 33. The connection is made by first hoisting the lower edge of support 28 up over bars 35 and 35', and then raising the top of support 28 until pins 39 and 41 can be inserted. The pins are retained in engagement by swiveling the handle portions thereof under a respective pair of retention platelets 53 welded to the legs 27 and 29.

Support 28 includes vertical side slots for tilting action to be discussed hereinafter.

Extending upwardly from the cross piece of the mounting support is a valve support plate 34 (FIG. 3) on which the four adjacent control valves 38, 40, 42 and 44 are mounted. These valves are of conventional construction to control the pressurized fluid in conduit 141 (FIG. 2) to the opposite ends of hydraulic cylinders on the scraper. Each valve includes an internal spool valve and a plunger extending out of the top of the valve housing. Links 46, 48, 50 and 52 are attached to clevises on the upper ends of the plungers (FIG. 3). These links are in turn attached to transverse rods which extend laterally between the upwardly protruding vertical support ears 56 and 58 which rotatably support them. Control handles 62, 64, 66 and 68 extending forwardly adjacent the drivers seat are affixed to the ends of these rods. Thus, downward or upward shifting of the control handles shifts the plungers in the valve housings to selectively control the pressurized fluid flow to all of the cylinders.

Support 28 also has a pair of vertically extending, laterally spaced guide tracks or slots 70 (FIG. 6) and 72 (FIG. 2). Slot 72 is formed between leg 29 and vertical plate 81. Slot 70 is formed by attachment of a U bracket to leg 27. A horizontally extending, elongated, laterally positioned slide bar element 74 has its ends retained in these slots. This bar is pivotally mounted at its center on a pin 23 on cross bar 25 (FIG. 7). One end (FIG. 6) of bar 74 includes a vertically extending boss 78 which interfits pivotally with a clevis 80 mounted to the lower end of rod 82 of fluid cylinder 84.

The upper end of fluid cylinder 84 is pivotally attached to a laterally extending portion 86 of plate 81 (FIG. 2). Extension and contraction of this fluid cylinder lowers and raises, respectively, the one end of the slide bar. This controls the vertical tilt of the bar and the entire unit from side to side of i.e. from end to end of the grader, as will be understood hereinafter. This enables the desired slant to be provided to the surface being operated upon.

Pivotally attached to this element 74 and extending rearwardly therefrom, generally perpendicular thereto, is a cantilever support beam 90. This support beam is preferably shaped like a trapezoid with its narrow portion to the rear, but may be of varied structural configuration.

The forward end of the beam includes a pair of forwardly extending flanges 92 and 94 at each side (FIG. These interfit with and receive a pair of rearwardly extending flanges 96 and 98, respectively, from slide element 74. Pins interconnect these to form a single horizontal pivotal axis between the beam and the slide bar.

The beam normally extends generally horizontally, but at a controlled vertical slant to the rear of the tractor. The particular position of the beam, hoisted or lowered, is controlled by fluid cylinder 100. It extends between the beam and fixed support 28. Its forward end is fixedly but pivotally secured to rearwardly and upwardly extending flanges 102 (FIG. 2) attached to cross member 28 of the support. The rearward end of the piston rod, extending from the cylinder, is pivotally connected between a pair of upwardly extending flanges 106 (FIGS. 2, 4 and 5) affixed to the rearward end of the beam.

Affixed to the bottom and the top of the beam, and extending rearwardly therefrom, is a pair of Vertically spaced mounting plates 110 and 112. Interfitting between these plates is a pair of forwardly extending plates 114 and 116 aflixed to a vertical portion 118 of the scraper blade mechanism. A vertical pin 120 interconnects these plates to provide a pivotal connection with a vertical axis between the scraper blade and the beam. The scraper blade itself 124 extends transversely of the center line through the beam, from side to side of the tractor. It is reinforced on its lower edge as usual. The forwardly curved blade may include a back-up panel 126.

Removably attached to the ends of the main blade are two small, forwardly directed side blades 128 and 130. These are desirable for some jobs but not for others such as cutting a ditch. Therefore, they are removably attached to the main blade assembly with releasable con nector means including pins 132 and 134 which slidably interfit with orificed flanges 133 and 135 on the rear of the blade assembly. These pins are held in place by suitable loosely fitted retention cross pins or keys 131.

Although the blade is shown directly perpendicular to the center line of beam 90 (FIG. 5), the forward to rearward position of the opposite ends of the blade may be controllably varied about the vertical pivotal axis pin 120. This variation is achieved by utilizing fluid cylinders and 142 which extend between the sides of beam 90 and the two end portions of the scraper blade on opposite sides of pin 120. A pair of flange 146 is mounted to one side of the beam for receiving the forward end of the piston rod from cylinder 142 with a pivotal connection. A second pair of flanges 148 is fixedly attached on the top of the blade to pivotally mount the opposite end cylinder 142. Likewise, a similar pair of flanges 150 is mounted to the opposite side of the beam 90, and flanges 152 are mounted to the opposite end above the blade for cylinder 140. Extension of one cylinder is accompanied by retraction of the opposite one to rotate the scraper blade on its vertical pivotal axis.

Extending rearwardly from the center of the scraper blade, in the opposite direction to beam 90, is a wheel mount 160. This wheel mount includes a pair of fixed, forwardly extending ears interfitting with a respective pair of upwardly extending flanges 162 and 164 on the rear of the scraper blade mechanism. Rotatably suspended beneath this wheel mount is a wheel 168, preferably of the airplane type, capable of being operated at a slant. This wheel is mounted on a horizontal rolling axle to the depending bracket of the wheel mount. The bracket is secured to the wheel mount on a vertical axis with an intermediate bearing 171. This allows free turning rotation of the entire wheel and bracket in 360 horizontally.

Positioned above the wheel mount is a forwardly extending fluid cylinder 172 for extending and contracting to raise and lower the wheel. The forward end of this cylinder is pivotally attached between a pair of flanges 176 on the top of the blade assembly. The rearward end of the extended piston rod is pivotally mounted between a pair of flanges 180 extending upwardly from the wheel mount. Extension of this fluid cylinder lowers the wheel by causing the wheel mount and wheel to vertically pivot about its pivotal axis between flanges 164 due to the pinned connection. This causes the scraper blade 124 to be raised. Contraction of the cylinder 172 likewise causes raising of the wheel mount and wheel to lower the scraper blade in depth. Thus the depth of the scraper blade is at all times exactly and accurately controlled with extension and contraction of this fluid cylinder controlled amounts. When desired, the wheel and wheel mount can be completely hoisted to the position illustrated in FIG. 2. This is especially useful when leveling large piles of dirt to spread it out since the wheel is then entirely out of the way. The dirt is merely pushed and pulled around with the blade, its general height being controlled with cylinder 100. When exact level grading is to be done, cylinder 172 is extended to lower the wheel to the surface.

The four manual valves 33, 40, 42 and 44 illustrated in FIG. 3 allow the driver to control cylinders 84, 100, 140-142, and 172. These valves each have a pair of outlets in the valve housing (FIG. 3) to which pressure hose connections are made. The two hoses from each valve extend to the opposite ends of the respective cylinders in conventional fashion to extend and retract the pistons therein. These connections are not shown in great detail since such are an obvious expedient to those in the art. The connections to cooperating cylinders 140 and 142 include four hoses, with one outlet of the respective valve being connected to the forward end of one cylinder and to the rearward end of the other cylinder, and the second valve outlet being connected to the opposite ends to cause retraction of one with extension of the other, and vice versa. Pressurized fluid is supplied to operate the valves through line 141 from a suitable hydraulic pump (not shown) mounted to the tractor and driven by the engine 18. This hydraulic pump may be the same pump employed for the hydraulic equipment on the front scoop loader 26 or a separate one.

When cylinder 172 is extended to place the wheel on the ground surface, cylinder 100 is freely floating in nature. That is, the piston and rod in cylinder 100 are allowed to float when the wheel is on the ground since the wheel and cylinder 172 control the particular depth of the blade. The valve and valve control handle for cylinder 100 therefore have four positions. The first is raising the blade assembly by allowing fluid pressure to contract the cylinder, the third is for lowering the blade by extending the cylinder, the second is to hold the blade in a selected position by preventing flow to the cylinder, and the fourth is for allowing a floating action of the cylinder by allowing bypassing of the fluid past the valve in either direction. By so doing, the cylinder is temporarily rendered inactive as a power means. The fixation of cylinder 172 creates a suspension beam combination which includes the wheel mount and the cantilever beam 90. The blade is thus suspended in the central portion, front to back, of this beam combination to form the transverse load, while the wheel 168 and the rear wheels of the tractor form the end supports therefor. The floating function of cylinder 100 is achieved by conventional means such as a bypass passage around the spool of its manual control valve. This can be readily manually achieved by shifting the control lever for this valve to a particular pre-set bypassing position.

Operation The novel scraper unit eliminates the need for a separate vehicle used for grading a road bed, a lawn area, or the like. To employ the scraper unit it is merely pinned to the rear of the tractor by interfitting cross rods 35 and 35 with slots 37, and inserting locking pins 39 and 41 in openings 43, 45 and 47. Then the hose connections are made with conventional quick disconnect hydraulic connectors to the pump driven by the engine. The unit is then ready for operation.

If the tractor is to be driven to the site of use, hydraulic cylinders 100 and 172 may be retracted to hoist the scraper blade a substantial distance off the ground, and to hoist the depth governing wheel and wheel mount into the air as illustrated for example in FIG. 2. At the site, if piles of dirt are to be first leveled off, the wheel is left up in the air, using the blade to level the dirt. The driver merely reaches over and grasps the appropriate one of the control handles 62, 64, 66 or 68 to raise and lower the blade. If then the surface is to be graded to a smooth surface at an exact level and slant, the appropriate handle is grasped and shifted to shift a valve and lower the wheel mount 160 by extending the fluid cylinder 172. First, however, cylinder 100 must be in a free floating condition by shifting its valve to a bypass position. This is done before the valve for cylinder 172 is shifted.

The particular forward to rearward angle from side to side of the scraper blade is then obtained by shifting the proper valve to actuate power cylinders 140 and 142, turning the scraper blade on its pivotal pin 120 about a vertical axis. Next, the vertical tilt from side to side of the blade is achieved by shifting the last valve to extend or contract fluid cylinder 84, to controllably tilt the one end of the support bar 74 and thus the entire blade mechanism, including the beam, blade, wheel mount, and wheel. The unit is then ready for operation.

During operation, the driver can constantly control the total depth of the blade by merely shifting the valve which controls fluid cylinder 172 to raise or lower the wheel mount, thereby lowering or raising the scraper blade exact amounts. Further, the particular vertical tilt can be varied readily to achieve the slant desired. Complete control with great versatility is had at all times over the unit. Even if the front tractor wheels go over a bump, the blade is only slightly affected due to the fact that it is removed from the front wheels so far, and due to its unique support arrangement. Consequently, no substantial ridges or gouges are caused.

When the scraper unit is no longer needed, it may be unpinned and hydraulically disconnected from the tractor and removed. Alternatively, it may be hoisted to its position illustrated in FIG. 2, out of the way, so that the re maining implements on the tractor can be used in conventional fashion.

The advantages of this unit, in economics, in versatility and flexibility, and in accurate control, will be readily apparent to those having ordinary skill in the art. Indeed, the unit has been received with enthusiasm by those presently in this field. Various additional advantages to those specifically set forth above will also occur to those in the art upon studying this preferred form of the invention. It is also conceivable that certain minor obvious modifications can be made in the particular structural components illustrated, within the concepts of the invention as set forth. Consequently, the invention is not to be limited merely by the particular preferred construction illustrated but only by the scope of the appended claims, and the reasonably equivalent structures to those defined therein.

I claim:

1. A versatile grader unit for a tractor comprising: a mounting support for fixed attachment to a tractor; a horizontally extending, vertically shiftable slide element retained on said support; an extension-retraction means vertically positioned between one end of said element and said support for controllably tilting said element; a horizontally extending cantilever beam pivotally mounted to said element on a horizontal pivot axis; extension-retraction means between said support and said beam to shift said beam vertically on said horizontal pivot axis; a scraper blade pivotally secured to the end of said beam opposite said support on a vertical pivot axis; a pair of extension-retraction means on opposite sides of said beam and extending between said beam and the opposite ends of said blade to turn said blade in a generally horizontal plane; a wheel mount having one end pivotally attached to said blade on a horizontal pivot axis, the other end extending away from said blade and supporting a wheel; and extension-retraction means between said wheel mount and said blade to hoist and lower said wheel mount on its horizontal pivot axis with respect to said blade to lower and raise said blade for depth control.

2. A versatile grader unit 'for a tractor comprising: a mounting support; a horizontally extending, vertically shiftable slide element retained on said support; an extension-retraction means vertically positioned between one end of said element and said support for controllably tilting said element; a horizontally extending cantilever beam mounted to said element; a scraper blade secured to the end of said beam opposite said element on a vertical pivot axis; a wheel mount having one end attached to said blade, the other end extending away from said blade and supporting a wheel; and means between said wheel mount and said blade to hoist and lower said wheel mount with respect to said blade to lower and raise said blade for depth control.

3. A grader unit for a tractor comprising: a mounting support; a horizontally extending element retained on said support; a horizontally extending cantilever beam mounted to said element on a horizontal pivot axis; powered extension means between said support and said beam to control the position of said beam vertically on said horizontal pivot axis; a scraper blade secured to the end of said beam opposite said element on a vertical pivot axis; a wheel mount having one end pivotally attached to said blade on a horizontal pivot axis, the other end extending away from said blade and supporting a wheel; and extension-retraction means between said wheel mount and said blade to hoist and lower said wheel mount on its horizontal pivot axis with respect to said blade to lower and raise said blade for depth control.

4. The unit in claim 3 wherein said powered extension means can become inactive to float, allowing said extension-retraction means to completely control blade height.

5. A grader unit for a tractor comprising: a mounting support; a horizontally extending transverse element retained on said support; a horizontally extending cantilever beam pivotally mounted to said element on a horizontal pivot axis and generally normal to said element; means between said support and said beam to shift said beam vertically on said horizontal pivot axis; a scraper blade pivotally secured to the end of said beam opposite said support on a vertical pivot axis; means on opposite sides of said beam extending between said beam and the opposite ends of said blade to turn said blade in a generally horizontal plane on said vertical pivot axis; a wheel mount having one end attached to said blade, the other end extending away from said blade and supporting a wheel; and means between said wheel mount and said blade to hoist and lower said wheel mount with respect to said blade, to lower and raise said blade for depth control.

6. A grader unit for a tractor comprising: a mounting support including vertical guide track means; a horizontally extending, vertically shiftable transverse slide element retained on said support in said track means; an extension-retraction means vertically positioned between one end of said element and said support for controllably tilting said element; a horizontally extending cantilever beam mounted to said element; means between said support and said beam to tilt said beam vertically on said element; a scraper blade secured to the end of said beam opposite said element on a vertical pivot axis; a wheel mount having one end attached to said blade, the other end extending away from said blade opposite to said beam and supporting a wheel; and means between said wheel mount and said blade to hoist and lower said wheel mount with respect to said blade, to lower and raise said blade for depth control, whereby the overall depth of said blade is controlled by the vertical position of said wheel, and the vertical tilt of said blade is independently achieved by tilting said slide element "to tilt said beam blade and wheel mount.

7. A grader unit comprising: support means including a horizontally extending transverse element pivotally mounted at its center and vertically shiftable at its ends, and a vertically extending power extension and contraction means connected between one end of said element and an additional part of said support means to pivot and thereby tilt said element; a beam combination having one end pivotally attached to said support means on a horizontal transverse pivot axis, and extending away therefrom, and having a wheel supporting the opposite end thereof; a horizontal pivot connection in the central portion of said beam combination; a scraper blade suspended from said beam combination adjacent said pivot connection; and adjustment holding means across said pivot connection capable of causing movement about said pivot connection to obtain desired vertical positioning of said blade, and of holding said connection and blade at the desired level.

8. The unit in claim 3 wherein said wheel mount and scraper blade are interconnected to allow said wheel mount to pivot to an elevated position with said wheel mount and wheel above said scraper blade, and said extension-contraction means is shiftable to move said wheel mount and wheel to said elevated position.

References Cited by the Examiner UNITED STATES PATENTS 1,713,048 5/1929 McMillan.

1,928,778 10/1933 Austin.

2,726,464 12/1955 White 37-169 3,032,902 5/1962 Shumaker 37180 3,123,923 3/1964 Calabrese 37-180 3,226,860 1/1966 McGee 37144 X FOREIGN PATENTS 897,725 5/ 1962 Great Britain.

ABRAHAM G. STONE, Primary Examiner.

R. L. HOLLISTER, Assistant Examiner. 

1. A VERSATILE GRADER UNIT FOR A TRACTOR COMPRISING: A MOUNTING SUPPORT FOR FIXED ATTACHMENT TO A TRACTOR; A HORIZONTALLY EXTENDING, VERTICALLY SHIFTABLE SLIDE ELEMENT RETAINED ON SAID SUPPORT; AN EXTENSION-RETRACTION MEANS VERTICALLY POSITIONED BETWEEN ONE END OF SAID ELEMENT AND SAID SUPPORT FOR CONTROLLABLY TILTING SAID ELEMENT; A HORIZONTALLY EXTENDING CANTILEVER BEAM PIVOTALLY MOUNTED TO SAID ELEMENT ON A HORIZONTAL PIVOT AXIS; EXTENSION-RETRACTION MEANS BETWEEN SAID SUPPORT AND SAID BEAM TO SHIFT SAID BEAM VERTICALLY ON SAID HORIZONTAL PIVOT AXIS; A SCRAPER BLADE PIVOTALLY SECURED TO THE END OF SAID BEAM OPPOSITE SAID SUPPORT ON A VERTICAL PIVOT AXIS; A PAIR OF EXTENSION-RETRACTION MEANS ON OPPOSITE SIDES OF SAID BEAM AND EXTENDING BETWEEN SAID BEAM AND THE OPPOSITE ENDS 